Piston-ring-finishing assembly



H. C. DOAN AND C. J. MARSON.

PISTON RING FINISHING ASSEMBLY.

APPLICATION FILED APR. 2, 19120.

' 1,380,136. l merma May 31,1921.

@CLM f/M. y WMM UNITED STATES PATENT OFFICE.

HARRY C. DOAN A ND CLIFFORD J. MAB/SON, 0F RICHMOND, INDIANA, ASSIGNORST0 D. & M. AUTOPARTS C0., 0F RICHMOND, INDIANA, A CORPORATION 0FINDIANA- PIsroN-RING-FINIsI-I'ING ASSEMBLY.

Specification of Letters Patent.

Patented May 31, 1921.

Application filed April 2,' 1920. Serial No. 370,632.

To all whom t may concern.'

Be it known that we, HARRY C. DoAN and CLIFFORD J. MARsoN, citizens ofthe United States, residing in the city of Richmond, in the county ofWayne, State of Indiana, have invented a new and usefulPiston-Ring-Finishing Assembly, of which tthe following is a full,clear, and comprehensive specification, the same being such as willenable others to make and use the same with exactitude.

In the production of piston rings it is necessary, in order to insurethe best results, that when the ring is completed and in its normalexpanded position, that the end portions of the ring shall not projectout beyond the true circle of the ring, which manifestly would be theresult if the ring was finished in closed position, that is with the endportions of the ring contacting with each other without the employmentof our invention, therefore to insure the ring forming a true circlewhen in its normal and finished condition is the paramount object of ourinvention.

Bro-adly stated, our object is to provide a piston ring finishingassembly whereby a quantity of uniinished piston rings may be arrangedin proper relations and clamped together whereby the entire lot may beplaced in a lathe for the purpose of dressing or machining theperipheries of all of the rings at one operation, and whereby the ringsafter being machinedy will each assume an absolutely true circle whenreleased from the assembly and when they are in operative condition in acylinder.

Other objects-and particular advantages of our invention will suggestthemselves to an expert in the course of the following de- Scriptlon.

The preferred means for carrying out the lprinciples of our invention ina practical and efficient manner is shown in the accompanying drawings,in which- Figure 1 is a slde elevation of a portion of our device,

showing a plurality of piston rings clamped together by our device asthe same would appear when laced in a machine lathe preparatory fornishing or Vmachining theperipheries of-the rings. Fig. 2 is a centrallongitudinal section as taken'throughthe parts shown in Fig. l, but inaddition there to showing the pot or container in which the rings areassembled whereby they are sprung together to be clamped. Fig. 3 is anend elevation of the pot, showing one of the rings positioned therein.And Fig. -t shows one of the completed rings alone.

Slmilar indices denote like parts throughout the several views.

l In order that the construction, the operation, and the principles ofour invention may be more fully understood and appreciated we will nowtake up a detailed description thereof in which we will set forth theseveral features as fully and as comprehensively as we may.

Referring now to the drawings in detail: Numeral l denotes the shapingpot, the saine being in the nature of a heavy tube, whose bore is thesame in cross section throughout its length, the bore or interior of thepot being round in cross section except at one point where it isslightly enlarged by reason of the segment or crescent 2 formed thereinas shown in Fig. 3. The interior of the pot is, therefore, such that allparts of the inner wall thereof are concentric with the center, exceptthe crescent 2 formed in one side thereof substantially as shown.

Numeral 3 denotes the arbor, which is of considerably less diameter thanis the interior of the pot 2. Secured on one end portion of the arbor 3is the permanent collar or supporting head 4, the diameter of said headbeing such as to permit it to enter the interior of the pot 1. The otherend of the arbor 3 is reduced in diameter and the reduced portionthereof is provided with the threads 5 which are adapted to receive thenut 6.

Numeral 74 denotes the movable head or supporting collar, the same beingadapted to slide on the arbor 3 and to tit the interior of the pot l,the same as does the head Numeral 8 denotes the central or iioatingcollar, this being ofthe same diameter as the heads 4: and 7 and likethe latter being slidable on the arbor 3. The collar 8 has a hub orflange 9 which is only for the purpose of retaining the collar 8 atright-angles to the arbor 3, that is giving it a larger bearing.

Letter A denotes each of the unfinished pistonlrings. Letter B denotesone of the finished piston rings after it has been removed from theclamp. The end portions of each of the rings are denoted by the lettersa and Z).

Numeral 10 denotes the driving arm which is secured in one end portionof the arbor 3 and it projects out at right-angles therefrom, to beengaged by the lathe-head whereby the arbor will be revolved with thelathe head.

Formed centrally in the ends of the arbor 3 are the sockets 11 and 12which are adapted to receive the pointed ends o-f the respective lathecenters 13 and 14, as shown in dotted lines in Fig. 1.

Modus opemndz':ln practice the arbor is first inserted in the pot 1,bringing the head 4 to approximately the position shown in Fig. 2. .Wenow insert a plurality of rings A into the pot 1 until the pot isapproximately one-half filled, with the rings contacting with the head4. We then insert the collar 8 in the pot, contacting it with the saidrings, after which the remainder of the rings are inserted in the potuntil the combined thickness of all of the rings in the pot, plus thecollar 8, is slightly more than the distance from the head 4 to theshoulder at the inner end of the threads 5. The head 7 is then broughtto position and contacted with the outermost ring in the pot, afterwhich the nut 6 is run on the threads 5 and` be located in the center ofthe `crescent 2,

thereby leaving the end portions of the rings free to expand. slightlybeyond the main circle of the interior of the pot.

After the nut has been tightened then the pot 1 may be slipped offendwise, thereby uncovering the rings but they will be retained in theposition to which they have been brought by the pot.

Next the arbor containing the rings is located in a lathe, beingcentered therein and sus ended by the lathe centersv 18 and 14.

ow as the rings are revolved by the lathe their peripheries may bemachined by a lathe bit in the usual manner, after which they areremoved from the lathe, the nut 6 may then be loosened and the rings,removed reversely to their placement on the arbor.

It is evident that by reason of the end portions a and 5 being free toproject into the crescent 2 that in the operation of machming the ringsthe peripheries of the parts aand Z) will be the first engaged by thedrill bit, and therefore the rings will be turnedl to a true circle intheir compressed condition, therefore when they are released and thering expands it is manifest that the end portions a and b will notproject out beyond the true circle line of the finished ring,

thereby attaining the paramount object of our invention. I

It is to be understood that various changes may be made in the specificconstruction, shape,y and arrangement of parts herein vshown withoutdeparting from the spirit of the invention and without sacrificing anyof the advantages thereof.

Having now fully shown and described our invention, what we claim anddesire to secure by Letters Patent of the United States is 1. In apiston ring nishing assembly, a

pot having a tubular aperture extending `length of the inner wall ofsaid pot being slightly enlarged out of true circle of the wall wherebywhen the rings are placed in the pot the end portions of the rings mayproject outward beyond the main circular line of said wall, allsubstantially as shown and described.

3. A pistn ring finishing assembly comprising a tubular forming pot, thesame having an aperture therethrough adapted lto receive a plurality ofcontracted piston rings, there being one portion of the wall of saidaperture which is slightly enlarged, said enlargement being crescentshaped and extendinv from end to end of the pot, the ends of the ringscontained in thel pot being located centrally of said enlargempnt of theinterior wall whereby the end portions of the rings may project outbeyond the line of said central aperture, all substantially as shown anddescribed.

4. A piston ring finishing assembly, comprising a tube having a boretherethrough longitudinally thereof which bore is of a diameter such asto receive compressed rings therein, said ,tube being enlarged at oneplace in its interior wall and extending from end to end thereof withthe end portions of the rings contained in the tube located centrally ofsaid enlargement, means for clamping together all of the rings locatedin the tube whereby when the rings are assembled and removed from thetube they will retain their compressed positions, all substantially asshown and described.

5. A piston ring forming assembly including a tubular pot having acircular bore therethrough with one portion of said bore enlarged fromend to end of the pot, heads for closing the ends of the pot, a collar1ocated centrally ofthe pot and dividing the rings contained in the pot,an arbor extending centrally through the pot and through said heads andcollar, and means for clamping said heads upon piston rings located inthe pot and in suchmanner as to permit the pot to be removed after therings are secured in clamped condition, all substantially as shown anddescribed.

6. That improvement in finishing piston rings which consists ininolosing a plurality of rings in compressed Condition with the endportions of the rings free to spring outward, then clamping the ringstogether in the shape to which they have been formed by the -inclosingmeans, then removing the inclosing means, next machining the peripheriesof the rings while in their clamped condition, and then releasing therings whereby they will assume their normal position each forming a truecircle, substantially as set forth and for the purposes specified. A

In ltestimony whereof we have hereunto subscribed our names to thisspecification in the presence of two subscribing witnesses.

'HARRY o. Donn. otirronn J. Manson.

Witnesses:

ROBERT W. RANDLE, M. E. RANDLE.

